Catheter introducers are routinely used for access to the arterial system, providing a means of entry into the interior of an artery while inhibiting blood loss during catheter procedures. For example, catheter introducers are used for introduction of balloon angioplasty catheters into the femoral artery of a patient for access to the coronary arteries via the ascending and descending aorta to perform percutaneous transluminal coronary angioplasty.
Catheter introducers typically comprise an elongated tubular member open at both ends (e.g., a sheath), a tubular dilator slidably positionable within the sheath, and a guide wire slidably positionable within the dilator. Catheter introducers can be introduced into an artery utilizing a standard insertion procedure, such as the Seldinger technique. In the Seldinger technique, the artery wall is pierced by a stylet and cannula, the stylet is removed, the guide wire is inserted through the cannula, and the cannula is removed from the artery. In order to facilitate insertion of a sheath through the artery tissue wall, a dilator is inserted into the sheath to penetrate through hardened portions of the tissue wall, such as calcified regions of the artery or scar tissue resulting from prior sheath insertion. The sheath and dilator may then be introduced over the guide wire until the distal tip of the sheath is positioned within the artery. Introduction of the sheath and dilator into the artery should be accomplished quickly and efficiently, with minimal damage to the artery wall.